The defeat of King Sombra is only the beginning of Celestia and Luna's troubles when they discover his daughter, Nightshade, also has strong magic. Her memory is erased and she is entrusted into the care of a loving family in the hope that she will not become like her father, but as she grows, her dangerous magic becomes a problem.

If Sombra were to ever return and seek revenge, the princesses fear that he might convince Nightshade to use her powers against them, unless they can successfully keep the truth from her.

After the mysterious disappearance of her father, Static Shimmer's mother does all she can to keep her safe and conceal the truth from her. However, as Static grows older and more independent, she discovers the horrors that await behind the gates to the Rainbow Factory in her search for her missing father. Just when she feels that all hope is gone, she meets a stallion who shows her that maybe her true colours are not lost forever. Can Static trust this troubled pony, or are the clutches of the Rainbow Factory inescapable?